Electric connector with relatively-movable terminals for outdoor, icing environment

ABSTRACT

An electric connector usable in an outdoor, icing environment for conducting current between spaced-apart, relatively movable parts. The connector comprises a tubular contact member, a rod contact member telescopically slidable therein, and two universal joints respectively mounting said contact members on said movable parts to permit angular movement of the contact members relative to said parts. A tubular sheath of flexible material encircles the portion of the rod contact member located outside said tubular contact member and has an external shape containing protuberances adapted to notch, and thereby weaken, any ice forming thereabout.

United States Patent [191 Badey et al.

[ ELECTRIC CONNECTOR WITII RELATIVELY-MOVABLE TERMINALS FOR OUTDOOR, ICING ENVIRONMENT [75] Inventors: Paul E. Badey, MediajJohn A.

Oppel, Aldan, both of Pa.

[73] Assignee: General Electric Company,

Philadelphia, Pa.

[22] Filed: Apr. 3, 1972 [21] Appl. No.: 240,493

[52] US. Cl 339/2 R [51] Int. Cl HOlr 39/64 [58] Field of Search 339/2 R, 2 A, 2 L, 339/2 RL [56] References Cited UNlTED STATES PATENTS 2,359,351 10/1944 Bruno 339/2 R 2,422,961 6/1947 Hallstrand 339/2 R Jan. 1,1974

3/1956 Droin 339/2 L 5/1959 Winkler 339/2 L Primary Examiner-George V. Larkin Att0rneyJ. Wesley Haubner et a1.

[57] ABSTRACT An electric connector usable in an outdoor, icing environment for conducting current between spacedapart, relatively movable parts. The connector comprises a tubular contact member, a rod contact member telescopically slidable therein, and two universal joints respectively mounting said contact members on said movable parts to permit angular movement of the contact members relative to said parts. A tubular sheath of flexible material encircles the portion of the rod contact member located outside said tubular contact member and has an external shape containing protuberances adapted to notch, and thereby weaken, any ice forming thereabout.

10 Claims, 2 Drawing Figures ELECTRIC CONNECTOR WITH RELATIVELY-MOVABLE TERMINALS FOR OUTDOOR, ICING ENVIRONMENT BACKGROUND ting damaging forces to the protected apparatus through the electrical connection.

One way of achieving such mechanical isolation is to use for the electrical connection a flexible conductor that has a relatively large amount of slack that permits the desired relative movement to occur without using up all the slack. A disadvantage of this approach is that such a conductor consumes an undue amount ofspace in a direction transverse of the conductor, particularly since the conductor might swing back and forth in a transverse direction in response to high winds.

SUMMARY An object of our invention is to provide a simple electrical connector which provides the desired mechanical isolation and yet consumes only a moderate amount of space in a transverse direction.

Another object is to provide an electrical connector of this type which employs sliding contacts and other relatively movable parts that are free to move without undue interference from heavy ice formations that may develop on the connector.

In carrying out our invention in one form, we provide a tubular contact member, a rod contact member telescopically slidable therein, and two universal joints respectively mounting said contact members on two spaced-apart terminals that are adapted to be secured to the parts between which current is to be conducted. The universal joints permit angular movement of each contact member with respect to its associated terminal member, and flexible conductive means carries current around the universal joints. A tubular sheath of flexible material encircles the portion of the rod contact member that is located outside the tubular contact member and is joined to portions of the connector in locations to prevent entry of foreign matter between said contact members. The sheath, which changes its length in response to relative movement of the contact members, has protuberances in its outer surface that are adapted to form notches in any ice forming thereabout, thus weakening theice formation and increasing its susceptibility to being fractured by forces produced by relative movement of the contact members.

BRIEF DESCRIPTION OF DRAWINGS For a better understanding of the invention, reference may be had to the following description taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a side elev'ational view, partly in section, showing a connector embodying one form of the present invention.

FIG. 2 is a sectional view along the line 2-2 of FIG. 7

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT Referring now to FIG. 1, there is shown an electrical connector 10 for providing an electrical connection between a pair of spaced-apart conductive parts 12 and 14. These parts 12 and 14 are the terminals of conventional electrical apparatus, for example, a disconnect switch and a circuit breaker, respectively, in an outdoor power station.

The connector 10 comprises a tubular contact member 16 and a rod contact member 18 telescopically slidable withing the tubular' contact member. These contact members are of a high conductivity metal, such as copper. The rod contact 18 is preferably formed from a tube that is provided with circumferentially spaced, axially-extending slots at its outer end to define resilient fingers 20 between adjacent pairs of slots. Preferably, each of these fingers is backed up by a suitably supported compression spring 22 that biases its corresponding finger in a radially-outward direction into high pressure engagement with the bore of the tubular contact member 16. The outer surface of fingers 20 and the bore of tubular contact member 16 are preferably silver-plated to provide for a high conductivity interface between these parts. It is to be noted that the bore of the tubular contact member 18 and the exterior of the rod contact member 16 are of a circular form in transverse cross-section so that the contact members are allowed rotational movement with respect to each other about the central longitudinal axis of the connector should the need arise.

The connector 10 further comprises spaced-apart terminals 25 and 26 at its opposite ends. Terminal 25 is bolted to apparatus part 12 and terminal 26 to apparatus part 14 to provide good electrical connections between the bolted-together parts. The outer tubular contact member 16 is mounted on terminal 25 by means comprising a universal joint 30 of conventional form. This universal joint 30 is best illustrated in the sectional view of FIG. 2, where it is shown as comprising a cross 32 pivotally mounted on terminal 25 by suitable bolts 34 journaled in the terminal 25. Bolts 34 serve as trunions mounting the cross for pivotal motion about an axis 35. The cross 32 further includes a cross shaft 36 on which a yoke member 38 is pivotally mounted to pivot about an axis 39 perpendicular to axis 35. Yoke member 38 is connected through an adapter 40 (FIG. 1) to the tubular contact member 16. This adapter 40 comprises a radially extending disk 42 which fits within tubular member 16 and is attached thereto by screws 44. v

The other contact member 18 is supported on the other terminal member 26 by means comprising a universal joint 50 substantially identical to previously described universal joint 30. In view of this identity, universal joint 50 will not be described in detail. An adapter 60 corresponding to previously described adapter 40 secures tubular rod contact 18 to yoke member 58 of the universal joint 50. For carrying current around each of the universal joints 30 and 50, suitable flexible conductive braids are utilized. Referring specifically to joint 30, conductive braids 70 are shown bolted at their opposite ends to terminal member and tubular contact member 16. Referring to joint 50, identical conductive braids 72 are bolted at their opposite ends to the other terminal 26 and rod contact 18.

The presence of the two universal joints and 50 and the above described ability to accommodate relative rotational movement of contact members 16 and 18 about central longitudinal axis 75 permit the apparatus part 12 to freely move in any angular direction with respect to apparatus part 14. In addition to such angular movement, there may also be movement of part 12 relative to part 14 along the longitudinal axis 75 of the connector. Such relative longitudinal movement along axis 75 is accompanied by sliding of rod contact 18 within tubular contact 16, permitting the connector to shorten or lengthen in response to such movement.

Since any angular and any longitudinal motion of parts 12 and 14 relative to each other are freely accommodated by connector 10, it will be apparent that each of these parts is freely movable in any direction relative to the other.

During any of the above-described relative motion, braids 70 and 72 carry current around the universal joints, and the sliding engagement between members 16 and 18 provides for current transfer between these parts.

For protecting the sliding surfaces of contacts 16 and 111 from foreign matter such as water and ice, a flexible tubular sheath 80 is provided. Sheath 80 is of rubber or a rubber-like material, such as Buna-S, reinforced with high strength fibers and has a substantially uniform wall thickness. This sheath 80 surrounds, or encircles, the portion of the rod contact 18 that is outside tubular contact member 16. The left-hand end of the sheath 80 fits around the tubular contact member 16 and is suitably secured thereto. The right-hand end of the sheath extends over the universal joint 50 at terminal member 26 and is suitably attached to the terminal member.

The external surface of the illustrated sheath 80 is of a corrugated form, characterized by a series of annular protuberances 82 extending around the circumference of the sheath and annular grooves 84 between the protuberances. Preferably, the protuberances 82 terminate in relatively sharp edges.

In some of the outdoor applications where we apply our connector, ice formations can develop on the connector, often building up in a tubular form of substantial thickness around the sheath 80. Because the sheath 80 has the protuberances 82 on its outer surface, the tubular ice 8 formation enveloping the sheath will have notches in its inner surface. These notches significantly weaken the ice formation and make it much more easily fractured by forces developed by relative motion between the parts of the connector 10.

More specifically, if tubular contact member 16 should move to the left relative to rod contact 18, any ice on the sheath 80 adhering to the tubular member 16 would be subjected to an axially-directed tensile force tending to fracture the ice, particularly at the abovedescribed notches. In addition to this axially directed tensile force, a radially-directed force is applied to the ice tending to load it circumferentially in tension. This latter force is derived from the tendency of the sheath to expand its inner diameter when elongated. More specifically, in response to such elongation, the grooved portions of the sheath tend to move radiallyoutward into alignment with generatrix A-B of a reference cylinder. This expansion applies the abovementioned radially directed force to the ice. The reinforcing fibers in the sheath enable the sheath to develop a substantial radially outward force in response to this elongation.

Should tubular contact members 16 move to the right, instead of the left, relative to contact member 18, the ice on sheath 8 0 is subjected to an axially directed compressive force that is effective in fracturing the ice in view of its weakness resulting from the notches therein. In addition to this axially directed force, the ice is subjected to a radially outward force derived from the forward edge 90 of tubular member 16 sliding beneath the grooved portion of the sheath. This forward edge 90 has a wedge form that separates the grooved portion of sheath from the outer surface of the rod contact member 18 and forces the grooved portion in a radially outward direction, thus loading the surrounding ice in tension circumferentially.

A similar wedge in the form of a ring 92 with a wedge surface 94 is provided on the rod contact member 16 at its right hand end. When the connector is shortened, the wedge surface 9 1 of ring 92 rides under the grooved portions of the sheath 80 forcing them radially outward to aid in fracturing any surrounding ice formation.

The above-described ice fracturing capabilities of our connector will enable the relatively movable parts of the connector to move in the manner described without undue interference from any ice formations on the connector. Any relative rotational movement of the contact members that might accompany the above relative longitudinal movement further aids in fracturing surrounding ice.

Although the illustrated sheath has an external surface containing spaced annular protuberances and annular grooves therebetween, other shapes can be used, provided such shapes are effective to produce at least one notch, and preferably many notches, in the interior surface of a surrounding ice formation that will significantly weaken the ice formation and make it more susceptible to fracture in response to relative movement of the connector parts.

For further protecting the internal parts of the connector from the entry of foreign matter, another tubular sheath 96 of flexible rubber-like material is provided around the left-hand universal joint 30. This sheath is connected at its respective opposite ends to the terminal 25 and the tubular contact member 16.

Additional protection against the entry of foreign matter between the contact members is provided by a suitable O-ring 97 mounted in an annular groove in the bore of tubular contact member 16 and slidably engaging the exterior of rod contact 18.

It will be apparent from the above-description that, as compared to a flexible conductor, our connector requires relatively little space in a transverse direction since it will not move out of its position shown if the interconnected apparatus parts 12 and 14 remain fixed. Accordingly, no significant amount of such transverse movement will be produced by winds and the like, assuming the parts 12 and M remain fixed.

Another advantage of my connector as compared to a flexible conductor is that it imposes little or no impact loads comparable to those developed when a flexible conductor is suddenly driven taut by high-velocity gusts of wind.

While we have shown and described a particular embodiment of our invention, it will be obvious to those skilled in the art that various changes and modifications may be made without-departing from our invention in its broader aspects; and we, therefore, intend herein to cover all such changes and modifications as fall within the true spirit and scope of our invention.

What we claim as new and desire to secure by Letters Patent of the United States is:

1. A connector usable in an outdoor, icing environment for conducting electric current between spacedapart first and second parts that can move with respect to each other by relatively large amounts under predetermined conditions, said connector comprising:

a. spaced-apart terminals adapted to be connected respectively to said parts,

b. a tubular contact member,

c. a rod contact member telescopically slidable within said tubular contact member,

d. means comprising a first universal joint for mounting said tubular contact member on said first terminal for angular motion with respect to said first terminal,

e. means comprising a second universal joint for mounting said rod contact on said second terminal for angular motion with respect to said second terminal,

f. flexible conductive means for carrying current around said first universal joint between said first terminal and said tubular contact member,

g. additional flexible conductive means for carrying current around said second universal joint between said second terminal and said rod contact member,

h. a tubular sheath of flexible material encircling the portion of said rod contact member that is located outside said tubular contact member, and

i. means joining said sheath to portions of said connector in locations to prevent entry of foreign matter between said contact members,

j. said sheath shortening in response to movement of said rod contact member further into said tubular contact member and elongating in response to movement of said rod contact member in a withdrawal direction from said tubular contact member,

k. said sheath having at least one protuberance in its outer surface that is adapted to form a notch in any ice that forms around said tubular sheath, thus weakening said ice formation and increasing its susceptibility to being fractured by forces produced by relative movement of said contact members.

2. The connector of claim 1 in which said protuberance has a relatively sharp edge that causes the notch developed thereby in any surrounding ice formation to have a relatively sharp-edge bottom for increasing the susceptibility of the ice to fracture.

3. The connector of claim 1 in which said sheath is of such a wall construction that the internal portions of said sheath move radially outward in response to sheath elongation, thus developing a radially-outward force on any surrounding ice when the sheath is elongated by relative contact movement.

4. The connector of claim 1 in which said sheath has an exterior of a corrugated form characterized by alternate protuberances and grooves adapted to notch any surrounding ice where the protuberances are located.

5. The connector of claim 4 in which some of said protuberances terminate in relatively sharp edges.

6. The connector of claim 4 in which: said sheath is of a thin-walled construction in which radially outward motion of the grooved portions of said sheath occurs in response to elongation of said sheath, thus developing a radially-outward force on any surrounding ice when the sheath is elongated by relative contact movement.

7. The connector of claim 1 in which said tubular contact member has an outer end of wedge-shaped configuration that wedges the sheath radially outward as said outer end slides between said sheath and said rod contact member during shortening of said connector, thereby providing additional ice-fracturing force.

8. The connector of claim 7 in which said rod contact member has a wedge-shaped portion on its outer periphery that slides within said sheath to wedge the sheath radially outward, thereby providing an additional ice-fracturing force.

9. The connector of claim 1 in which said rod contact member has a wedge-shaped portion on its outer periphery that slides within said sheath to wedge the sheath radially outward, thereby providing an additional ice-fracturing force.

10. The connector of claim 1 in which said tubular contact member has a bore receiving said rod contact member and engaging the exterior thereof, said bore and said exterior being of a form that allows relative rotational movement of said contact members about the longitudinal axis of said connector. 

1. A connector usable in an outdoor, icing environment for conducting electric current between spaced-apart first and second parts that can move with respect to each other by relatively large amounts under predetermined conditions, said connector comprising: a. spaced-apart terminals adapted to be connected respectively to said parts, b. a tubular contact member, c. a rod contact member telescopically slidable within said tubular contact member, d. means comprising a first universal joint for mounting said tubular contact member on said first terminal for angular motion with respect to said first terminal, e. means comprising a second universal joint for mounting said rod contact on said second terminal for angular motion with respect to said second terminal, f. flexible conductive means for carrying current around said first universal joint between said first terminal and said tubular contact member, g. additional flexible conductive means for carrying current around said secoNd universal joint between said second terminal and said rod contact member, h. a tubular sheath of flexible material encircling the portion of said rod contact member that is located outside said tubular contact member, and i. means joining said sheath to portions of said connector in locations to prevent entry of foreign matter between said contact members, j. said sheath shortening in response to movement of said rod contact member further into said tubular contact member and elongating in response to movement of said rod contact member in a withdrawal direction from said tubular contact member, k. said sheath having at least one protuberance in its outer surface that is adapted to form a notch in any ice that forms around said tubular sheath, thus weakening said ice formation and increasing its susceptibility to being fractured by forces produced by relative movement of said contact members.
 2. The connector of claim 1 in which said protuberance has a relatively sharp edge that causes the notch developed thereby in any surrounding ice formation to have a relatively sharp-edge bottom for increasing the susceptibility of the ice to fracture.
 3. The connector of claim 1 in which said sheath is of such a wall construction that the internal portions of said sheath move radially outward in response to sheath elongation, thus developing a radially-outward force on any surrounding ice when the sheath is elongated by relative contact movement.
 4. The connector of claim 1 in which said sheath has an exterior of a corrugated form characterized by alternate protuberances and grooves adapted to notch any surrounding ice where the protuberances are located.
 5. The connector of claim 4 in which some of said protuberances terminate in relatively sharp edges.
 6. The connector of claim 4 in which: said sheath is of a thin-walled construction in which radially outward motion of the grooved portions of said sheath occurs in response to elongation of said sheath, thus developing a radially-outward force on any surrounding ice when the sheath is elongated by relative contact movement.
 7. The connector of claim 1 in which said tubular contact member has an outer end of wedge-shaped configuration that wedges the sheath radially outward as said outer end slides between said sheath and said rod contact member during shortening of said connector, thereby providing additional ice-fracturing force.
 8. The connector of claim 7 in which said rod contact member has a wedge-shaped portion on its outer periphery that slides within said sheath to wedge the sheath radially outward, thereby providing an additional ice-fracturing force.
 9. The connector of claim 1 in which said rod contact member has a wedge-shaped portion on its outer periphery that slides within said sheath to wedge the sheath radially outward, thereby providing an additional ice-fracturing force.
 10. The connector of claim 1 in which said tubular contact member has a bore receiving said rod contact member and engaging the exterior thereof, said bore and said exterior being of a form that allows relative rotational movement of said contact members about the longitudinal axis of said connector. 